This Background is intended to provide the basic context of this patent application and it is not intended to describe a specific problem to be solved. A highly comprehensive on-line product catalog is vital for e-commerce success. Keeping a product catalog current in the face of innumerable product introductions and new manufacturers can be a Herculean task. Typically, on-line catalogs build product entries by relying on product feeds and information from multiple sources. However, different merchants or other sources (such as review sites, manufacturer listings, etc.) may provide different subsets of information or data for a same product. Furthermore, the different sources may provide their product information using different schemas and with wide variation in how product attributes are represented. For example, different sources may use schemas that name product attributes differently (e.g. “dimensions” vs. “length,” “width,” and “height”). Different sources may describe the attributes differently (e.g. “megapixels” or “pixels”). From the perspective of a user of the product catalog, separate product listings for a same product from each supplying provider would be a suboptimal experience. Similarly, mere concatenation of duplicate conceptual product information would also be suboptimal. The wide diversity of types, structures of information and data itself from a wide variety and number of data sources provide a formidable challenge in populating product descriptions that are succinct, comprehensive, meaningful and useful to a user of an on-line product catalog.